docs: def load_parameters(filename):
          """ Load parameters stored in file ``filename``.
  
          ``p = nonlinear_fit.load_p(filename)`` is used to recover the
          values of fit parameters dumped using ``fit.dump_p(filename)`` (or
          ``fit.dump_pmean(filename)``) where ``fit`` is of type
          :class:`lsqfit.nonlinear_fit`. The layout of the returned
          parameters ``p`` is the same as that of ``fit.p`` (or
          ``fit.pmean``).
          """
          warnings.warn(
              "nonlinear_fit.load_parameters deprecated; use pickle.load or gvar.load instead",
              DeprecationWarning,
              )
          with open(filename,"rb") as f:
              return pickle.load(f)